Improvement in hot-air furnaces



fitters game (time.

JOHN W. WE N TWO RTH, OF MINNEAPOLIS, MlNNE SOTA. Letters Patent No. 85,774, dated January 12, 1869.

IMPROVEMENT IN HOT-AIR. FURNACES.

The Schedule referred to in these Letters Patent and making part of the same nesota, have invented certain new and useful Improve ments in Hot-Air Furnaces; and I do hereby. declare that the following is alnll, clear, and exact description I thereof, reference beiu g had to the accompanying drawings, making part of this specification, and to the letters of reference marked thereon, like letters indicating like parts wherever they occur.

To enableothers skilled in the art to construct and use my invention, I will proceed to describe it.

This invention relates to furnaces, and consists in a buildings.

In the drawings- Figure 1 is a longitudinal vertical section on the line 50-2: of fig. 2.

. Figure 2 is a veri imil cross-section on the line y-y of fig. 1.

A is the fire-box, in which the fuel-is placed, and from which the smoke passes ofi through the large flue B into the lower end of the chamber F, and from this chamber, through the tubes 0, back to the front end of the furnace, into the chamber E; froin thence, through another set of pipes, D, into the upper end of the chamber F, and out, through the pipe 0, to

nevel construction of a-hot-air furnace for-heating the chimney, as shown-by the red arrows in fig. 1.

The fire-box A has an air-chamber, J, shown in figs.

1 and 2, around three sides, and from which chamber air is admitted to the lire-box, through the small per-- i IZLlJlOllS c, as shown by the black arrows, the air being admitted to the chamber J through the openings covered by slides, K, said slides being operated by the rods d, extending out through the front of the case, as shown in fig. 1.

Entrance is gained to the chamber E through the door G, to the fire-box through the door H, and to the ash-pit by door '1, all as shown in fig. 1. The chamber F is, provided with a horizontal butterfly-valve, I2, as shown in fig. 1, lying between the tubes 0 and D, and below the pipe 0, and is operated by the rod 1), pivoted to an arm, 0, on one end of the valve, as shown in figs. l and 2. V

The object of this valve is to form a partition across the chamber 1*, and thus force the smoke, entering the lower end of said chamber through the flue B, to pass through the flues 0 and D before it can escape, and

1 thus utilize much of the heat that would otherwise pass ofl'to the chimney.

When, however, a direct draught is required, as when starting the fire, the valve I 'is turned so as to stand vertically, and thus allow the smoke to pass directly from the flue B up through chamber F, and out through pipe 0.

The pipes 0 rise gradually from the rear to the front, and the pipes D from'the front to the rear of the furnace, as shown in ;1, thus aiding the smoke in its passage through them, and allowing the soot and ashes to be more readily removed than if they were horizontal. r

By. opening. the door G, the frontendsof all the tubes are exposed, so that a brush or other suitable instrument may be introduced, and the ashes, soot, 850., shoved out their rear ends, falling down through the chamber F and flue B into the fire-box, the valve L being turned-so as to allow the ashes, 850., to fall past it, and also permitting a direct draught, so that the tubes'may be cleaned while the furnace is in operation.-

The whole furnace, as described, is surrounded with a case, M, of metal or brick, as desired, and out through the side of which the pipe Opasses.

This case is provided with openings near its base for' the admission ofcold air, and an opening, N, at the top, for the escape of the heated air, which is conducted from said opening, through suitable pipes, to any point or points desired.-

The air, entering at the bottom of the case llfy'passes around over the exterior surfaces of the tubes-O and D, and flue B, and then out through N to theidistribnting-pipcs.

Among the advantages of this furnace are, its simplicity, cheapness, the great amount of surface exposed to the action of the fire, and for the radiation-of heat, and the convenience in removing soot, &c., from the tubes.

Having thus described my invention,

What I claim, is- A hot-air furnace, consisting of the fire-box A, chamhers E and F, with the tubes (J and D, inclined-as represented, and the valve L, all constructed and arranged to operate as described.

Witnesses: JOHN W. WENTWORTH.

E. S. J ONES, W. H. LEONARD. 

